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                                                                     EXHIBIT 4.6


                          REGISTRATION RIGHTS AGREEMENT


     This REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made as of
December 10, 2003 by and among ATR Acquisition, LLC, a Delaware limited
liability company (the "LLC"), Atrium Corporation, a Delaware corporation (the
"Company"), and the parties listed on the signature pages hereto under the
heading "Investors" (each, an "Investor" and collectively, the "Investors").

     WHEREAS, the LLC, and the Investors are parties to that certain Amended and
Restated Limited Liability Company Agreement, dated as of December 10, 2003 (as
amended from time to time, the "LLC Agreement"); the Company, the LLC and
certain Investors from time to time are or may be parties to that certain
Stockholders Agreement, dated as of December 10, 2003 (as amended from time to
time, the "Stockholders Agreement"); and the LLC and the Company are parties to
that certain Stock Purchase Agreement, dated as of December 10, 2003 (the
"Purchase Agreement"); and

     WHEREAS, as an inducement to the Investors to enter into and consummate the
transactions contemplated by the LLC Agreement and the Stockholders Agreement
and the LLC to enter into and consummate the transactions contemplated by the
Purchase Agreement, the Company has agreed to provide certain registration
rights to the Investors and their transferees of their equity securities of the
Company as provided herein.

     NOW, THEREFORE, in consideration of the foregoing, the parties agree as
follows:

          1. Definitions. For purposes of this Agreement:

             (a) "Affiliate" of a specified Person means a Person that directly,
or indirectly through one or more intermediaries, controls, or is controlled by,
or is under common control with, such specified Person.

             (b) "Common Stock" means shares of common stock, par value $0.01,
of the Company and any common stock issued (or issuable upon the conversion or
exercise of any warrant, right or other security which is issued) with respect
to the Common Stock by way of a stock dividend, stock split, combination of
shares, share subdivision, share exchange, recapitalization, merger,
consolidation or other reorganization.

             (c) "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

             (d) "Form S-3" means such form under the Securities Act as in
effect on the date hereof or any registration form under the Securities Act
subsequently adopted by the SEC, which permits inclusion or incorporation of
substantial information by reference to other documents filed by the Company
with the SEC.

             (e) "Holder" means any Person owning or having the right to acquire
Registrable Securities (including any member of the LLC), or any assignee
thereof in accordance with Section 11 hereof.

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             (f) "Initiating Holders" means the Holder(s) initiating a
registration request under section 2(a) below.

             (g) "Investor Request" means a request by Holders that in the
aggregate own at least 15% of the Operating Company Share Equivalents (as such
term is defined in the LLC Agreement).

             (h) "Person" means any individual, partnership, limited liability
company, joint venture, corporation, association, trust or any other entity or
organization.

             (i) "Register," "registered," and "registration" refer to a
registration effected by preparing and filing a registration statement or
similar document in compliance with the Securities Act, and the declaration or
ordering of effectiveness of such registration statement or document.

             (j) "Registrable Securities" means (i) any of the Rollover Shares
as such term is defined in the LLC Agreement and (ii) any Common Stock issued or
issuable in redemption of any membership interests in the LLC in accordance with
the terms of the LLC Agreement; provided, however, that shares of Common Stock
shall cease to be Registrable Securities once a registration statement with
respect to the sale of such shares shall have become effective under the
Securities Act and such shares shall have been disposed of in accordance with
such registration statement or such shares shall have been sold to the public in
accordance with Rule 144 promulgated by the SEC under the Securities Act (or any
successor provision).

             (k) "SEC" means the Securities and Exchange Commission.

             (l) "Securities Act" means the Securities Act of 1933, as amended.

             (m) "Violation" means any of the following statements, omissions or
violations: (i) any untrue statement or alleged untrue statement of a material
fact contained in a registration statement filed under or referred to in this
Agreement, including any preliminary prospectus or final prospectus contained
therein or any amendments or supplements thereto or any documents filed under
state securities or "blue sky" laws in connection therewith, (ii) the omission
or alleged omission to state therein a material fact required to be stated
therein, or necessary to make the statements therein not misleading, or (iii)
any violation or alleged violation by the Company of the Securities Act, the
Exchange Act, any state securities law or any rule or regulation promulgated
under the Securities Act, the Exchange Act or any state securities law arising
from, relating to or in connection with the offer and sale of Registrable
Securities pursuant to this Agreement.

          2. Request for Registration.

             (a) If at any time and from time to time the Company shall receive
a written Investor Request that the Company file a registration statement under
the Securities Act, then the Company shall, within ten (10) days of the receipt
thereof, give written notice of such request to all Holders and, subject to the
limitations of Section 2(b) below, shall file (as expeditiously as practicable,
and in any event within ninety (90) days of the receipt of such request in
connection with the initial public offering of the Company's securities and
within sixty


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(60) days of the receipt of any other such request) and use its best efforts to
effect, a registration statement under the Securities Act with respect to all
Registrable Securities which the Holders request to be registered within thirty
(30) days of the mailing of such notice by the Company in accordance with
Section 19 below; provided; however, that a Holder shall not be entitled hereby
to request, and the Company shall not be obligated to effect, a registration
that would constitute the Company's initial registration of its common equity.

             (b) If the Initiating Holders intend to distribute the Registrable
Securities covered by their request by means of an underwriting, they shall so
advise the Company as a part of their request made pursuant to this Section 2,
and the Company shall include such information in the written notice referred to
in Section 2(a). In such event, the right of any Holder to include such Holder's
Registrable Securities in such registration shall be conditioned upon such
Holder's participation in such underwriting and the inclusion of such Holder's
Registrable Securities in the underwriting (unless otherwise mutually agreed by
a majority in interest of the Initiating Holders and such Holder) to the extent
provided herein. A majority in interest of the Holders of Registrable Securities
participating in the underwriting, with the consent of the Company which shall
not be unreasonably withheld, shall select the managing underwriter or
underwriters in such underwriting. All Holders proposing to distribute their
securities through such underwriting shall (together with the Company as
provided in Section 4(f)) enter into an underwriting agreement in customary form
with the underwriter or underwriters so selected for such underwriting;
provided, however, that no Holder (or any of their assignees) shall be required
to make any representations, warranties or indemnities except as they relate to
such Holder's ownership of shares and authority to enter into the underwriting
agreement and to such Holder's intended method of distribution, and the
liability of such Holder shall be limited to an amount equal to the net proceeds
from the offering received by such Holder. Notwithstanding any other provision
of this Section 2, if the underwriter advises a Holder that marketing factors
require a limitation of the number of shares to be underwritten, then the Holder
shall so advise the Company and the Company shall so advise all Holders of
Registrable Securities which would otherwise be underwritten pursuant hereto,
and the number of shares of Registrable Securities that may be included in the
underwriting shall be allocated as follows: (i) first, among holders of
Registrable Securities that have elected to participate in such underwritten
offering, in proportion (as nearly as practicable) to the aggregate amount of
Registrable Securities held by all such holders, until such holders have
included in the underwriting all shares requested by such holders to be
included, (ii) second, among all other holders of Common Stock, if any, that
have the right and have elected to participate in such underwritten offering, in
proportion (as nearly as practicable) to the amount of Common Stock owned by
such holders and (iii) third, any Common Stock being registered by the Company.
Without the consent of a majority in interest of the Holders of Registrable
Securities participating in a registration referred to in Section 2(a), no
securities other than Registrable Securities shall be covered by such
registration if the inclusion of such other securities would result in a
reduction of the number of Registrable Securities covered by such registration
or included in any underwriting or if, in the opinion of the managing
underwriter, the inclusion of such other securities would adversely impact the
marketing of such offering.

             (c) The Company shall be obligated to effect only three (3)
registrations pursuant to an Investor Request under this Section 2 (an offering
which is not consummated shall not be counted for this purpose); provided,
however, that in each case the


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Company shall be obligated to effect as many registrations (but not more than
one (1) per six-month period) as may be requested by Holders of Registrable
Securities pursuant to any Investor Request in the event and so long as (i) each
such registration includes Registrable Securities with an aggregate value (as of
the time of request) of at least one million dollars ($5,000,000) and (ii)
registration pursuant to Form S-3 or any similar "short-form" registration
statement is available.

          3. Company Registration. If the Company proposes to register
(including for this purpose a registration effected by the Company for
stockholders other than the Investors) any of its stock or other equity
securities under the Securities Act in connection with the public offering of
such securities solely for cash (other than a registration on Form S-8 (or
similar or successor form) relating solely to the sale of securities to
participants in a Company stock plan or to other compensatory arrangements to
the extent includable on Form S-8 (or similar or successor form), or a
registration on Form S-4 (or similar or successor form)), the Company shall, at
such time, promptly give each Holder written notice of such registration. Upon
the written request of each Holder given within thirty (30) days after mailing
of such notice by the Company in accordance with Section 19, the Company shall,
subject to the provisions of Section 8, use its best efforts to cause to be
registered under the Securities Act all of the Registrable Securities that each
such Holder has requested to be registered.

          4. Obligations of the Company. Whenever required under this Agreement
to effect the registration of any Registrable Securities, the Company shall, as
expeditiously as reasonably possible:

             (a) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
of a majority of the Registrable Securities being registered thereunder, keep
such registration statement effective for up to one hundred eighty (180) days or
until the Holders have completed the distribution referred to in such
registration statement, whichever occurs first (but in any event for at least
any period required under the Securities Act); provided that a reasonable time
before filing such registration statement or any amendments thereto, the Company
will furnish to the Holders copies of all such documents proposed to be filed in
order to allow Holders to review and comment thereon.

             (b) Prepare and file with the SEC such amendments and supplements
to such registration statement and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement.

             (c) Furnish to the Holders such number of copies of such
registration statement and of each amendment and supplement thereto (in each
case including all exhibits), such number of copies of the prospectus contained
in such registration statement (including each preliminary prospectus and any
summary prospectus) and any other prospectus filed under Rule 424 under the
Securities Act, in conformity with the requirements of the Securities Act, and
such other documents as Holders may reasonably request in order to facilitate
the disposition of Registrable Securities owned by them.


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             (d) Use its best efforts to register and qualify the securities
covered by such registration statement for offer and sale under such other
securities or "blue sky" laws of such states or jurisdictions as shall be
reasonably requested by the Holders; provided that the Company shall not be
required in connection therewith or as a condition thereto (i) to qualify to do
business in any state or jurisdiction where it would not otherwise be required
to qualify but for the requirements of this clause (d) or (ii) to file a general
consent to service of process in any such state or jurisdiction.

             (e) Use diligent efforts to cause all Registrable Securities
covered by such registration statement to be registered with or approved by such
other governmental agencies or authorities as may be necessary by virtue of the
Company's business or operations to enable the seller or sellers thereof to
consummate the disposition of such Registrable Securities.

             (f) In the event of any underwritten public offering, enter into
and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering.

             (g) Notify each Holder of Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any event
of which it has knowledge as a result of which the prospectus included in such
registration statement, as then in effect, includes an untrue statement of a
material fact or omits to state a material fact required to be stated therein or
necessary to make the statements therein not misleading in the light of the
circumstances then existing.

             (h) Notify each Holder of Registrable Securities covered by such
registration statement and such Holder's underwriters, if any, and confirm such
advice in writing: (i) when the registration statement has become effective,
(ii) when any post-effective amendment to the registration statement becomes
effective and (iii) of any request by the SEC for any amendment or supplement to
the registration statement or prospectus or for additional information.

             (i) Notify each Holder of Registrable Securities if at any time the
SEC should institute or threaten to institute any proceedings for the purpose of
issuing, or should issue, a stop order suspending the effectiveness of the
registration statement. Upon the occurrence of any of the events mentioned in
the preceding sentence, the Company will use its best efforts to prevent the
issuance of any such stop order or to obtain the withdrawal thereof as soon as
possible. The Company will advise each Holder of Registrable Securities promptly
of any order or communication of any public board or body addressed to the
Company suspending or threatening to suspend the qualification of any
Registrable Securities for sale in any jurisdiction.

             (j) Furnish, at the request of any Holder requesting registration
of Registrable Securities pursuant to this Agreement, (i) on the date that such
Registrable Securities are delivered to the underwriters for sale in connection
with a registration pursuant to this Agreement, if such securities are being
sold through underwriters, or, if such securities are not being sold through
underwriters, on the date that the registration statement with respect to such


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securities becomes effective, an opinion, dated such date, of the counsel
representing the Company for the purposes of such registration, in form and
substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any, and to the Holders requesting
registration of Registrable Securities and (ii) on the date that the
registration statement with respect to such securities becomes effective, a
"comfort" letter dated such date, from the independent certified public
accountants of the Company, in form and substance as is customarily given by
independent certified public accountants to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities, and, if such securities are
being sold through underwriters, a reaffirmation of such letter on the date that
such Registrable Securities are delivered to the underwriters for sale.

             (k) Cause all such Registrable Securities to be listed on each
securities exchange on which similar securities issued by the Company are then
listed and if not so listed, to be listed on the NASD automated quotation system
and, if listed on the NASD automated quotation system, use its best efforts to
have such Registrable Securities quoted on the NASDAQ National Market.

             (l) make available for inspection by any seller of Registrable
Securities, any underwriter participating in any disposition pursuant to such
registration statement and any attorney accountant or other agent retained by
any such seller or underwriter, all financial and other records, pertinent
corporate documents and properties of the Company, and cause the Company's
officers, directors, employees and independent accountants to supply all
information reasonably requested by any such seller, underwriter, attorney,
accountant or agent in connection with such registration statement.

             (m) provide a transfer agent and registrar for all such Registrable
Securities not later than the effective date of such registration statement.

             (n) As soon as practicable after the effective date of the
registration statement, and in any event within sixteen (16) months thereafter,
have "made generally available to its security holders" (within the meaning of
Rule 158 under the Securities Act) an earning statement (which need not be
audited) covering a period of at least twelve (12) months beginning after the
effective date of the registration statement and otherwise complying with
Section 11(a) of the Securities Act.

          5. Furnish Information. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to this Agreement with
respect to the Registrable Securities of any selling Holder that such Holder
shall furnish to the Company such information regarding itself, the Registrable
Securities held by it, and the intended method of disposition of such securities
as shall be required to effect the registration of such Holder's Registrable
Securities. If any registration statement or comparable statement under the
Securities Act refers to an Investor or any of its affiliates, by name or
otherwise, as the holder of any securities of the Company then, unless counsel
to the Company advises the Company that the Securities Act requires that such
reference be included in any such statement, each such holder shall have the
right to require the deletion of such reference to itself and its affiliates.


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          6. Expenses of Demand Registration. All expenses, other than
underwriting discounts and commissions relating to Registrable Securities,
incurred in connection with registrations, filings or qualifications pursuant to
Section 2, including without limitation all registration, filing and
qualification fees, printers' and accounting fees, fees and disbursements of
counsel for the Company and the reasonable fees and disbursements of one counsel
(selected by a majority in interest of the selling Holders) for the selling
Holders shall be borne by the Company.

          7. Expenses of Company Registration. The Company shall bear and pay
all expenses incurred in connection with any registration, filing or
qualification of Registrable Securities with respect to the registrations
pursuant to Section 3 for each Holder, including without limitation all
registration, filing and qualification fees, printers' and accounting fees
relating or apportionable thereto and the fees and disbursements of one counsel
for the selling Holders (selected by the Holders of a majority of the
Registrable Securities being registered), but excluding underwriting discounts
and commissions relating to Registrable Securities.

          8. Underwriting Requirements. In connection with any offering
initiated by the Company involving an underwriting of shares being issued by the
Company, the Company shall not be required under Section 3 to include any
Holder's securities in such underwriting unless such Holder accepts the terms of
the underwriting as agreed upon between the Company and the underwriters
selected by it, and then only in such quantity as will not, in the opinion of
the underwriters, exceed the largest number of securities requested to be
included in such offering which can be sold without having an adverse effect on
such offering by the Company; provided, however, that no Holder participating in
such underwriting shall be required to make any representations, warranties or
indemnities except as they relate to such Holder's ownership of shares and
authority to enter into the underwriting agreement and to such Holder's intended
method of distribution, and the liability of such Holder shall be limited to an
amount equal to the net proceeds from the offering received by such Holder. If
the total number of securities, including Registrable Securities, requested by
stockholders to be included in such offering (or in any other offering in which
Holders shall have the right to include Registrable Securities pursuant to
Section 3) exceeds the largest number of securities that the underwriters
reasonably believe can be sold without having an adverse effect on such
offering, then the Company shall be required to include in the offering only
that number of such securities, including Registrable Securities, which the
underwriters believe will not have an adverse effect on such offering, and the
number of shares that may be included in the underwriting shall be allocated as
follows: (i) first, that number of shares sought to be registered by the
Company, (ii) second, among all Holders of Registrable Securities that have
elected to participate in such underwritten offering, in proportion (as nearly
as practicable) to the amount of Registrable Securities owned by such Holders
and (iii) thereafter, to the extent additional securities may be included in
such offering, to other selling stockholders, if any, pro rata according to the
total number of securities entitled to be included therein owned by each such
other selling stockholder or in such other proportions as shall mutually be
agreed to by such other selling stockholders.

          9. Indemnification. In the event any Registrable Securities are
included in a registration statement under this Agreement:


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             (a) The Company will indemnify and hold harmless each Holder, its
heirs, personal representatives and assigns, each of such Holder's partners,
each of such Holder's and each of such Holder's partners' officers, directors,
partners, members, employees and affiliates, any underwriter (as defined in the
Securities Act) for such Holder and each Person, if any, who controls such
Holder or underwriter within the meaning of the Securities Act or the Exchange
Act against any losses, claims, damages or liabilities (joint or several) to
which they may become subject under the Securities Act, the Exchange Act or any
other federal or state law, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon a
Violation; and the Company will pay to each such indemnified party, as incurred,
any legal or other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, damage, liability, or action;
provided, however, that the indemnity agreement contained in this Section 9(a)
shall not apply to amounts paid in settlement of any such loss, claim, damage,
liability or action if such settlement is effected without the consent of the
Company (which consent shall not be unreasonably withheld), nor shall the
Company be liable in any such case to a particular indemnified party for any
such loss, claim, damage, liability or action to the extent that it arises out
of or is based upon a Violation which occurs in reliance upon and in conformity
with written information furnished expressly for use in connection with such
registration by such indemnified party.

             (b) Each selling Holder will indemnify and hold harmless the
Company, each of its directors, each of its officers who has signed the
registration statement, each Person, if any, who controls the Company within the
meaning of the Securities Act, any underwriter, any other Holder selling
securities in such registration statement and any controlling Person of any such
underwriter or other Holder, against any losses, claims, damages or liabilities
(joint or several) to which any of the foregoing Persons may become subject,
under the Securities Act, the Exchange Act or other federal or state law,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereto) arise out of or are based upon any Violation, in each case to the
extent (and only to the extent) that such Violation occurs in reliance upon and
in conformity with written information furnished by such Holder expressly for
use in connection with such registration; and each such Holder will pay, as
incurred, any legal or other expenses reasonably incurred by any Person intended
to be indemnified pursuant to this Section 9(b), in connection with
investigating or defending any such loss, claim, damage, liability, or action;
provided, however, that the indemnity agreement contained in this Section 9(b)
shall not apply to amounts paid in settlement of any such loss, claim, damage,
liability or action if such settlement is effected without the consent of the
Holder, which consent shall not be unreasonably withheld; and, provided further,
that in no event shall the liability of any Holder under this Section 9(b)
exceed the net proceeds from the offering received by such Holder and in no
event shall a selling Holder have any liability to the extent that any Violation
occurs as a result of information provided by such selling Holder that was
subsequently corrected but was not disseminated by the Company in accordance
with the Securities Act.

             (c) Promptly after receipt by an indemnified party under this
Section 9 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 9, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to


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assume the defense thereof with counsel mutually satisfactory to such
indemnifying parties, acting reasonably, and reasonably satisfactory to the
indemnified party; provided, however, that an indemnified party shall have the
right to retain its own counsel, with the fees and expenses to be paid by the
indemnifying party or parties, as the case may be, if representation of such
indemnified party by the counsel retained by the indemnifying party or parties,
as the case may be, would be inappropriate due to actual or potential differing
interests between such indemnified party and any other party represented by such
counsel in such proceeding. The failure to deliver written notice to any
indemnifying party within a reasonable time of the commencement of any such
action shall not relieve such indemnifying party of any liability to the
indemnified party under this Section 9, except if, and only to the extent that,
such indemnifying party is actually prejudiced thereby; and such failure to
deliver written notice to any such indemnifying party will not relieve it of any
liability that it may have to any indemnified party otherwise than under this
Section 9. An indemnifying party may settle any action or claim under this
Section 9 at any time without the consent of the indemnified party so long as
such settlement involves no cost or liability to the indemnified party and
includes an unconditional release of the indemnified party from all liability
with respect to such claim or action.

             (d) The obligations of the Company and Holders under this Section 9
shall survive the completion of any offering of Registrable Securities in a
registration statement under this Agreement and otherwise.

             (e) Any indemnity agreements contained herein shall be in addition
to any other rights to indemnification or contribution which any indemnified
party may have pursuant to law or contract and shall remain operative and in
full force and effect regardless of any investigation made or omitted by or on
behalf of any indemnified party.

             (f) If a court of competent jurisdiction holds that the foregoing
indemnity is unavailable, then the indemnifying party shall contribute to the
amount paid or payable by the indemnified party as a result of such losses,
claims, damages, liabilities or expenses (i) in such proportion as is
appropriate to reflect the relative benefits received by the indemnifying party
on the one hand and the indemnified party on the other (taking into
consideration, among other things, the fact that the provision of the
registration rights and indemnification hereunder is a material inducement to
the Investors to purchase Registrable Securities) or (ii) if the allocation
provided by clause (i) above is not permitted by applicable law or provides a
lesser sum to the indemnified party than the amount hereinafter calculated, in
such proportion as is appropriate to reflect not only the relative benefits
received by the indemnifying party on the one hand and the indemnified party on
the other (taking into consideration, among other things, the fact that the
provision of the registration rights and indemnification hereunder is a material
inducement to the Investors to purchase Registrable Securities) but also the
relative fault of the indemnifying party and the indemnified party as well as
any other relevant equitable considerations. The relative fault shall be
determined by reference to, among other things, whether the Violation relates to
information supplied by, or on behalf of, the indemnifying party or the
indemnified party and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such untrue statement or
omission. No Person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any Person who was not guilty of such fraudulent misrepresentation.
Notwithstanding anything to the contrary in this Section 9, no Holder shall be


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required, pursuant to this Section 9, to contribute any amount in excess of the
net proceeds received by such indemnifying party from the sale of securities in
the offering to which the losses, claims, damages, liabilities or expenses of
the indemnified party relate.

         10. Reports Under the Exchange Act. With a view to making available to
the Holders the benefits of Rule 144 under the Securities Act and any other rule
or regulation of the SEC that may at any time permit a Holder to sell securities
of the Company to the public without registration or pursuant to a registration
on Form S-3, the Company agrees at all times after 90 days after any
registration statement covering a public offering of securities of the Company
under the Securities Act shall have become effective, to:

             (a) make and keep public information available, as those terms are
understood and defined in Rule 144 under the Securities Act;

             (b) use its best efforts (without unreasonable expense) to enable
the Holders to utilize Form S-3 for the sale of their Registrable Securities;

             (c) file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and the Exchange Act;
and

             (d) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144 under
the Securities Act (at any time after the effective date of the first
registration statement filed by the Company) and the Securities Act and Exchange
Act (at any time after it has become subject to such reporting requirements) or
that it qualifies as a registrant whose securities may be resold pursuant to
Form S-3 (at any time it so qualifies), (ii) a copy of the most recent annual or
quarterly report of the Company and such other reports and documents so filed by
the Company, and (iii) such other information as may be reasonably requested in
availing any Holder of any rule or regulation of the SEC, which permits the
selling of any such securities without registration or pursuant to such form.

         11. Assignment of Registration Rights. The rights to cause the Company
to register Registrable Securities pursuant to this Agreement may be assigned to
one or more transferees or assignees of the Registrable Securities or membership
interests in the LLC owned by such Holder; provided, that any assignment of
Registrable Securities or any membership interest in the LLC shall be subject to
the terms and conditions of the LLC Agreement and the Stockholders Agreement,
and provided, further, that in each case such transferee or assignee delivers to
the Company a written instrument by which such transferee or assignee agrees to
be bound by the obligations imposed on Holders under this Agreement to the same
extent as if such transferee or assignee was a party hereto. Except as
specifically permitted in the preceding sentence, neither this Agreement nor any
Holder's rights or privileges under this Agreement can be assigned or
transferred in whole or in part without the prior written consent of the other
parties.

         12. No Other Registration Rights; Limitations on Subsequent
Registration Rights. The Company, represents and warrants to each Investor that,
upon the execution of this Agreement by all of the parties hereto, no
"registration rights" relating to securities of the


                                       10
<PAGE>

Company and granted by the Company will exist on the date hereof other than
pursuant to this Agreement. From and after the date of this Agreement, the
Company shall not, without the prior written consent of Investors holding a
majority of the Registrable Securities then outstanding, enter into any
agreement with any holder or prospective holder of any securities of the
Company, which would allow such holder or prospective holder (a) to include such
securities in any registration filed under this Agreement, unless under the
terms of such agreement, such holder or prospective holder may include such
securities in any such registration only to the extent that the inclusion of
such holder's or prospective holder's securities will not reduce the amount of
the Registrable Securities of any Investor which is included therein or (b) to
request a registration.

         13. "Market Stand-Off " Agreement. Each Holder hereby agrees that,
during the period of ninety (90) days following the effective date of a
registration statement of the Company filed under the Securities Act in
connection with an underwritten offering of equity securities (and, in the case
of the initial public offering of the Company's securities, one hundred eighty
(180) days), it shall not, if requested by the Company and such underwriter,
sell or otherwise transfer or dispose of (other than to donees, affiliates or
partners who agree to be similarly bound) any Common Stock or any securities of
the Company convertible into Common Stock held by it, except Common Stock
included in such registration or Common Stock transferred pursuant to the
redemption described in Section 4.5 of the LLC Agreement. No Investor shall be
bound by this Section 13 unless each officer, director and other stockholder of
the Company holding in excess of 1% of the then outstanding common share
equivalents of the Company shall have complied with this Section 13.

         14. Amendment; Waiver. Any provision of this Agreement may be amended
only with the written consent of the Company and Investors holding a majority of
the Registrable Securities then held by Investors. The observance of any
provision of this Agreement may be waived (either generally or in a particular
instance and either retroactively or prospectively) only with the written
consent of the party to be charged, provided that the Holders of a majority of
the Registrable Securities then outstanding may act on behalf of all Holders of
Registrable Securities. Any amendment or waiver effected in accordance with this
Section 14 shall be binding upon each Holder of Registrable Securities at the
time outstanding, each future Holder of all such securities, and the Company.

         15. Changes in Registrable Securities. If, and as often as, there are
any changes in the Registrable Securities by way of stock split, stock dividend,
combination or reclassification, or through merger, consolidation,
reorganization or recapitalization, or by any other means, appropriate
adjustment shall be made in the provisions of this Agreement, as may be
required, so that the rights and privileges granted hereby shall continue with
respect to the Registrable Securities as so changed. Without limiting the
generality of the foregoing, the Company will require any successor by merger or
consolidation to assume and agree to be bound by the terms of this Agreement, as
a condition to any such merger or consolidation.

         16. Entire Agreement. This Agreement constitutes the full and entire
understanding and agreement among the parties with regard to the subject matter
hereof and supersedes all prior agreements. Nothing in this Agreement, express
or implied, is intended to confer upon any Person, other than the parties hereto
and their respective Affiliates, successors


                                       11
<PAGE>

and assigns, any rights, remedies, obligations, or liabilities under or by
reason of this Agreement, except as expressly provided herein.

         17. Governing Law.

             (a) This Agreement shall be governed by and construed under the
laws of the State of New York as applied to agreements among New York residents
entered into and to be performed entirely within New York.

             (b) The jurisdiction and venue in any action brought by any party
hereto pursuant to this Agreement shall properly lie in any federal or state
court located in the State of New York. By execution and delivery of this
Agreement, each party hereto irrevocably submits to the jurisdiction of such
courts for himself or itself and in respect of his or its property with respect
to such action. The parties irrevocably agree that venue would be proper in such
court, and hereby waive any objection that such court is an improper or
inconvenient forum for the resolution of such action. The parties further agree
that the mailing by certified or registered mail, return receipt requested, of
any process required by any such court shall constitute valid and lawful service
of process against them, without necessity for service by any other means
provided by statute or rule of court.

             (c) WAIVER OF JURY TRIAL. EACH OF THE PARTIES HERETO HEREBY
KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES ANY RIGHTS IT MAY HAVE TO A
TRIAL BY JURY IN RESPECT OF ANY LITIGATION BASED HEREON OR ARISING OUT OF, UNDER
OR IN CONNECTION WITH THIS AGREEMENT, ANY OF THE OTHER AGREEMENTS OR ANY COURSE
OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER ORAL OR WRITTEN) OR ACTIONS
OF THE INVESTORS.

         18. Successors and Assigns. The provisions hereof shall inure to the
benefit of, and be binding upon, the successors, permitted assigns (as provided
in Section 11), heirs, executors and administrators of the parties hereto.

         19. Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon receipt by the party to be notified (including by
telecopier, receipt confirmed) or three (3) days after deposit with the United
States Post Office, by registered or certified mail, postage prepaid and
addressed to the party to be notified (a) if to a party other than the Company,
at such party's address set forth on the books and records of the Company or at
such other address as such party shall have furnished the Company in writing,
or, until any such party so furnishes an address to the Company, then to and at
the address of the last holder of the shares covered by this Agreement who has
so furnished an address to the Company, or (b) if to the Company, at its address
set forth at the end of this Agreement, or at such other address as the Company
shall have furnished to the parties in writing.

         20. Severability. Any invalidity, illegality or limitation on the
enforceability of this Agreement or any part thereof, by any party whether
arising by reason of the law of the respective party's domicile or otherwise,
shall in no way affect or impair the validity, legality or


                                       12
<PAGE>

enforceability of this Agreement with respect to other parties. If any provision
of this Agreement shall be judicially determined to be invalid, illegal or
unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

         21. Titles and Subtitles. The titles of the Sections of this Agreement
are for convenience of reference only and are not to be considered in construing
this Agreement.

         22. Delays or Omissions; Remedies Cumulative. It is agreed that no
delay or omission to exercise any right, power or remedy accruing to the parties
shall impair any such right, power or remedy, nor shall it be construed to be a
waiver of any such breach or default, or any acquiescence therein, or of any
similar breach or default thereafter occurring; nor shall any waiver of any
single breach or default be deemed a waiver of any other breach or default
theretofore or thereafter occurring. It is further agreed that any waiver,
permit, consent or approval of any kind or character by a party of any breach or
default under this Agreement, or any waiver by a party of any provisions or
conditions of this Agreement must be in writing and shall be effective only to
the extent specifically set forth in writing and that all remedies, either under
this Agreement, or by law or otherwise afforded to a party, shall be cumulative
and not alternative.

         23. Attorneys' Fees. If any action at law or in equity is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

         24. Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument. Facsimile counterpart signatures shall be
acceptable.


                                       13
<PAGE>

         IN WITNESS WHEREOF, the parties hereto have executed this Registration
Rights Agreement as of the date first above written.


                                        THE COMPANY:

                                        ATRIUM CORPORATION

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:

                                        INVESTORS:

                                        KAT GROUP, L.P.

                                        By: JLK Operations, Inc., its general
                                            partner

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                        KAT HOLDINGS, L.P.

                                        By: KAT Group, L.P., its general partner

                                        By: JLK Operations, Inc., its general
                                            partner

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                        ML IBK POSITIONS, INC.

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                       14
<PAGE>

                                        MERRILL LYNCH VENTURES, L.P. 2001

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                        UBS CAPITAL AMERICAS II, LLC

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:
                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                        ATR ACQUISITION, LLC

                                            By:
                                               --------------------------------
                                               Print name:
                                               Title:


                                       15